| blob | dcb0593b4a66348a204a44fee3366c5da0848ad1 |
1 # x86 configuration
2 mainmenu "Linux Kernel Configuration for x86"
4 # Select 32 or 64 bit
5 config 64BIT
6 bool "64-bit kernel" if ARCH = "x86"
7 default ARCH = "x86_64"
8 ---help---
9 Say yes to build a 64-bit kernel - formerly known as x86_64
10 Say no to build a 32-bit kernel - formerly known as i386
12 config X86_32
13 def_bool !64BIT
15 config X86_64
16 def_bool 64BIT
18 ### Arch settings
19 config X86
20 def_bool y
21 select HAVE_AOUT if X86_32
22 select HAVE_READQ
23 select HAVE_WRITEQ
24 select HAVE_UNSTABLE_SCHED_CLOCK
25 select HAVE_IDE
26 select HAVE_OPROFILE
27 select HAVE_PERF_EVENTS if (!M386 && !M486)
28 select HAVE_IOREMAP_PROT
29 select HAVE_KPROBES
30 select ARCH_WANT_OPTIONAL_GPIOLIB
31 select ARCH_WANT_FRAME_POINTERS
32 select HAVE_DMA_ATTRS
33 select HAVE_KRETPROBES
34 select HAVE_OPTPROBES
35 select HAVE_FTRACE_MCOUNT_RECORD
36 select HAVE_DYNAMIC_FTRACE
37 select HAVE_FUNCTION_TRACER
38 select HAVE_FUNCTION_GRAPH_TRACER
39 select HAVE_FUNCTION_GRAPH_FP_TEST
40 select HAVE_FUNCTION_TRACE_MCOUNT_TEST
41 select HAVE_FTRACE_NMI_ENTER if DYNAMIC_FTRACE
42 select HAVE_SYSCALL_TRACEPOINTS
43 select HAVE_KVM
44 select HAVE_ARCH_KGDB
45 select HAVE_ARCH_TRACEHOOK
46 select HAVE_GENERIC_DMA_COHERENT if X86_32
47 select HAVE_EFFICIENT_UNALIGNED_ACCESS
48 select USER_STACKTRACE_SUPPORT
49 select HAVE_REGS_AND_STACK_ACCESS_API
50 select HAVE_DMA_API_DEBUG
51 select HAVE_KERNEL_GZIP
52 select HAVE_KERNEL_BZIP2
53 select HAVE_KERNEL_LZMA
54 select HAVE_KERNEL_LZO
55 select HAVE_HW_BREAKPOINT
56 select HAVE_MIXED_BREAKPOINTS_REGS
57 select PERF_EVENTS
58 select ANON_INODES
59 select HAVE_ARCH_KMEMCHECK
60 select HAVE_USER_RETURN_NOTIFIER
62 config INSTRUCTION_DECODER
63 def_bool (KPROBES || PERF_EVENTS)
65 config OUTPUT_FORMAT
66 string
67 default "elf32-i386" if X86_32
68 default "elf64-x86-64" if X86_64
70 config ARCH_DEFCONFIG
71 string
72 default "arch/x86/configs/i386_defconfig" if X86_32
73 default "arch/x86/configs/x86_64_defconfig" if X86_64
75 config GENERIC_TIME
76 def_bool y
78 config GENERIC_CMOS_UPDATE
79 def_bool y
81 config CLOCKSOURCE_WATCHDOG
82 def_bool y
84 config GENERIC_CLOCKEVENTS
85 def_bool y
87 config GENERIC_CLOCKEVENTS_BROADCAST
88 def_bool y
89 depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
91 config LOCKDEP_SUPPORT
92 def_bool y
94 config STACKTRACE_SUPPORT
95 def_bool y
97 config HAVE_LATENCYTOP_SUPPORT
98 def_bool y
100 config MMU
101 def_bool y
103 config ZONE_DMA
104 def_bool y
106 config SBUS
107 bool
109 config NEED_DMA_MAP_STATE
110 def_bool (X86_64 || DMAR || DMA_API_DEBUG)
112 config NEED_SG_DMA_LENGTH
113 def_bool y
115 config GENERIC_ISA_DMA
116 def_bool y
118 config GENERIC_IOMAP
119 def_bool y
121 config GENERIC_BUG
122 def_bool y
123 depends on BUG
124 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
126 config GENERIC_BUG_RELATIVE_POINTERS
127 bool
129 config GENERIC_HWEIGHT
130 def_bool y
132 config GENERIC_GPIO
133 bool
135 config ARCH_MAY_HAVE_PC_FDC
136 def_bool y
138 config RWSEM_GENERIC_SPINLOCK
139 def_bool !X86_XADD
141 config RWSEM_XCHGADD_ALGORITHM
142 def_bool X86_XADD
144 config ARCH_HAS_CPU_IDLE_WAIT
145 def_bool y
147 config GENERIC_CALIBRATE_DELAY
148 def_bool y
150 config GENERIC_TIME_VSYSCALL
151 bool
152 default X86_64
154 config ARCH_HAS_CPU_RELAX
155 def_bool y
157 config ARCH_HAS_DEFAULT_IDLE
158 def_bool y
160 config ARCH_HAS_CACHE_LINE_SIZE
161 def_bool y
163 config HAVE_SETUP_PER_CPU_AREA
164 def_bool y
166 config NEED_PER_CPU_EMBED_FIRST_CHUNK
167 def_bool y
169 config NEED_PER_CPU_PAGE_FIRST_CHUNK
170 def_bool y
172 config HAVE_CPUMASK_OF_CPU_MAP
173 def_bool X86_64_SMP
175 config ARCH_HIBERNATION_POSSIBLE
176 def_bool y
178 config ARCH_SUSPEND_POSSIBLE
179 def_bool y
181 config ZONE_DMA32
182 bool
183 default X86_64
185 config ARCH_POPULATES_NODE_MAP
186 def_bool y
188 config AUDIT_ARCH
189 bool
190 default X86_64
192 config ARCH_SUPPORTS_OPTIMIZED_INLINING
193 def_bool y
195 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
196 def_bool y
198 config HAVE_EARLY_RES
199 def_bool y
201 config HAVE_INTEL_TXT
202 def_bool y
203 depends on EXPERIMENTAL && DMAR && ACPI
205 # Use the generic interrupt handling code in kernel/irq/:
206 config GENERIC_HARDIRQS
207 def_bool y
209 config GENERIC_HARDIRQS_NO__DO_IRQ
210 def_bool y
212 config GENERIC_IRQ_PROBE
213 def_bool y
215 config GENERIC_PENDING_IRQ
216 def_bool y
217 depends on GENERIC_HARDIRQS && SMP
219 config USE_GENERIC_SMP_HELPERS
220 def_bool y
221 depends on SMP
223 config X86_32_SMP
224 def_bool y
225 depends on X86_32 && SMP
227 config X86_64_SMP
228 def_bool y
229 depends on X86_64 && SMP
231 config X86_HT
232 def_bool y
233 depends on SMP
235 config X86_TRAMPOLINE
236 def_bool y
237 depends on SMP || (64BIT && ACPI_SLEEP)
239 config X86_32_LAZY_GS
240 def_bool y
241 depends on X86_32 && !CC_STACKPROTECTOR
243 config ARCH_HWEIGHT_CFLAGS
244 string
245 default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
246 default "-fcall-saved-rdi -fcall-saved-rsi -fcall-saved-rdx -fcall-saved-rcx -fcall-saved-r8 -fcall-saved-r9 -fcall-saved-r10 -fcall-saved-r11" if X86_64
248 config KTIME_SCALAR
249 def_bool X86_32
250 source "init/Kconfig"
251 source "kernel/Kconfig.freezer"
253 menu "Processor type and features"
255 source "kernel/time/Kconfig"
257 config SMP
258 bool "Symmetric multi-processing support"
259 ---help---
260 This enables support for systems with more than one CPU. If you have
261 a system with only one CPU, like most personal computers, say N. If
262 you have a system with more than one CPU, say Y.
264 If you say N here, the kernel will run on single and multiprocessor
265 machines, but will use only one CPU of a multiprocessor machine. If
266 you say Y here, the kernel will run on many, but not all,
267 singleprocessor machines. On a singleprocessor machine, the kernel
268 will run faster if you say N here.
270 Note that if you say Y here and choose architecture "586" or
271 "Pentium" under "Processor family", the kernel will not work on 486
272 architectures. Similarly, multiprocessor kernels for the "PPro"
273 architecture may not work on all Pentium based boards.
275 People using multiprocessor machines who say Y here should also say
276 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
277 Management" code will be disabled if you say Y here.
279 See also <file:Documentation/i386/IO-APIC.txt>,
280 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
281 <http://www.tldp.org/docs.html#howto>.
283 If you don't know what to do here, say N.
285 config X86_X2APIC
286 bool "Support x2apic"
287 depends on X86_LOCAL_APIC && X86_64 && INTR_REMAP
288 ---help---
289 This enables x2apic support on CPUs that have this feature.
291 This allows 32-bit apic IDs (so it can support very large systems),
292 and accesses the local apic via MSRs not via mmio.
294 If you don't know what to do here, say N.
296 config SPARSE_IRQ
297 bool "Support sparse irq numbering"
298 depends on PCI_MSI || HT_IRQ
299 ---help---
300 This enables support for sparse irqs. This is useful for distro
301 kernels that want to define a high CONFIG_NR_CPUS value but still
302 want to have low kernel memory footprint on smaller machines.
304 ( Sparse IRQs can also be beneficial on NUMA boxes, as they spread
305 out the irq_desc[] array in a more NUMA-friendly way. )
307 If you don't know what to do here, say N.
309 config NUMA_IRQ_DESC
310 def_bool y
311 depends on SPARSE_IRQ && NUMA
313 config X86_MPPARSE
314 bool "Enable MPS table" if ACPI
315 default y
316 depends on X86_LOCAL_APIC
317 ---help---
318 For old smp systems that do not have proper acpi support. Newer systems
319 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
321 config X86_BIGSMP
322 bool "Support for big SMP systems with more than 8 CPUs"
323 depends on X86_32 && SMP
324 ---help---
325 This option is needed for the systems that have more than 8 CPUs
327 if X86_32
328 config X86_EXTENDED_PLATFORM
329 bool "Support for extended (non-PC) x86 platforms"
330 default y
331 ---help---
332 If you disable this option then the kernel will only support
333 standard PC platforms. (which covers the vast majority of
334 systems out there.)
336 If you enable this option then you'll be able to select support
337 for the following (non-PC) 32 bit x86 platforms:
338 AMD Elan
339 NUMAQ (IBM/Sequent)
340 RDC R-321x SoC
341 SGI 320/540 (Visual Workstation)
342 Summit/EXA (IBM x440)
343 Unisys ES7000 IA32 series
344 Moorestown MID devices
346 If you have one of these systems, or if you want to build a
347 generic distribution kernel, say Y here - otherwise say N.
348 endif
350 if X86_64
351 config X86_EXTENDED_PLATFORM
352 bool "Support for extended (non-PC) x86 platforms"
353 default y
354 ---help---
355 If you disable this option then the kernel will only support
356 standard PC platforms. (which covers the vast majority of
357 systems out there.)
359 If you enable this option then you'll be able to select support
360 for the following (non-PC) 64 bit x86 platforms:
361 ScaleMP vSMP
362 SGI Ultraviolet
364 If you have one of these systems, or if you want to build a
365 generic distribution kernel, say Y here - otherwise say N.
366 endif
367 # This is an alphabetically sorted list of 64 bit extended platforms
368 # Please maintain the alphabetic order if and when there are additions
370 config X86_VSMP
371 bool "ScaleMP vSMP"
372 select PARAVIRT
373 depends on X86_64 && PCI
374 depends on X86_EXTENDED_PLATFORM
375 ---help---
376 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
377 supposed to run on these EM64T-based machines. Only choose this option
378 if you have one of these machines.
380 config X86_UV
381 bool "SGI Ultraviolet"
382 depends on X86_64
383 depends on X86_EXTENDED_PLATFORM
384 depends on NUMA
385 depends on X86_X2APIC
386 ---help---
387 This option is needed in order to support SGI Ultraviolet systems.
388 If you don't have one of these, you should say N here.
390 # Following is an alphabetically sorted list of 32 bit extended platforms
391 # Please maintain the alphabetic order if and when there are additions
393 config X86_ELAN
394 bool "AMD Elan"
395 depends on X86_32
396 depends on X86_EXTENDED_PLATFORM
397 ---help---
398 Select this for an AMD Elan processor.
400 Do not use this option for K6/Athlon/Opteron processors!
402 If unsure, choose "PC-compatible" instead.
404 config X86_MRST
405 bool "Moorestown MID platform"
406 depends on PCI
407 depends on PCI_GOANY
408 depends on X86_32
409 depends on X86_EXTENDED_PLATFORM
410 depends on X86_IO_APIC
411 select APB_TIMER
412 ---help---
413 Moorestown is Intel's Low Power Intel Architecture (LPIA) based Moblin
414 Internet Device(MID) platform. Moorestown consists of two chips:
415 Lincroft (CPU core, graphics, and memory controller) and Langwell IOH.
416 Unlike standard x86 PCs, Moorestown does not have many legacy devices
417 nor standard legacy replacement devices/features. e.g. Moorestown does
418 not contain i8259, i8254, HPET, legacy BIOS, most of the io ports.
420 config X86_RDC321X
421 bool "RDC R-321x SoC"
422 depends on X86_32
423 depends on X86_EXTENDED_PLATFORM
424 select M486
425 select X86_REBOOTFIXUPS
426 ---help---
427 This option is needed for RDC R-321x system-on-chip, also known
428 as R-8610-(G).
429 If you don't have one of these chips, you should say N here.
431 config X86_32_NON_STANDARD
432 bool "Support non-standard 32-bit SMP architectures"
433 depends on X86_32 && SMP
434 depends on X86_EXTENDED_PLATFORM
435 ---help---
436 This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
437 subarchitectures. It is intended for a generic binary kernel.
438 if you select them all, kernel will probe it one by one. and will
439 fallback to default.
441 # Alphabetically sorted list of Non standard 32 bit platforms
443 config X86_NUMAQ
444 bool "NUMAQ (IBM/Sequent)"
445 depends on X86_32_NON_STANDARD
446 depends on PCI
447 select NUMA
448 select X86_MPPARSE
449 ---help---
450 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
451 NUMA multiquad box. This changes the way that processors are
452 bootstrapped, and uses Clustered Logical APIC addressing mode instead
453 of Flat Logical. You will need a new lynxer.elf file to flash your
454 firmware with - send email to <Martin.Bligh@us.ibm.com>.
456 config X86_SUPPORTS_MEMORY_FAILURE
457 def_bool y
458 # MCE code calls memory_failure():
459 depends on X86_MCE
460 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
461 depends on !X86_NUMAQ
462 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
463 depends on X86_64 || !SPARSEMEM
464 select ARCH_SUPPORTS_MEMORY_FAILURE
466 config X86_VISWS
467 bool "SGI 320/540 (Visual Workstation)"
468 depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
469 depends on X86_32_NON_STANDARD
470 ---help---
471 The SGI Visual Workstation series is an IA32-based workstation
472 based on SGI systems chips with some legacy PC hardware attached.
474 Say Y here to create a kernel to run on the SGI 320 or 540.
476 A kernel compiled for the Visual Workstation will run on general
477 PCs as well. See <file:Documentation/sgi-visws.txt> for details.
479 config X86_SUMMIT
480 bool "Summit/EXA (IBM x440)"
481 depends on X86_32_NON_STANDARD
482 ---help---
483 This option is needed for IBM systems that use the Summit/EXA chipset.
484 In particular, it is needed for the x440.
486 config X86_ES7000
487 bool "Unisys ES7000 IA32 series"
488 depends on X86_32_NON_STANDARD && X86_BIGSMP
489 ---help---
490 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
491 supposed to run on an IA32-based Unisys ES7000 system.
493 config SCHED_OMIT_FRAME_POINTER
494 def_bool y
495 prompt "Single-depth WCHAN output"
496 depends on X86
497 ---help---
498 Calculate simpler /proc/<PID>/wchan values. If this option
499 is disabled then wchan values will recurse back to the
500 caller function. This provides more accurate wchan values,
501 at the expense of slightly more scheduling overhead.
503 If in doubt, say "Y".
505 menuconfig PARAVIRT_GUEST
506 bool "Paravirtualized guest support"
507 ---help---
508 Say Y here to get to see options related to running Linux under
509 various hypervisors. This option alone does not add any kernel code.
511 If you say N, all options in this submenu will be skipped and disabled.
513 if PARAVIRT_GUEST
515 source "arch/x86/xen/Kconfig"
517 config VMI
518 bool "VMI Guest support (DEPRECATED)"
519 select PARAVIRT
520 depends on X86_32
521 ---help---
522 VMI provides a paravirtualized interface to the VMware ESX server
523 (it could be used by other hypervisors in theory too, but is not
524 at the moment), by linking the kernel to a GPL-ed ROM module
525 provided by the hypervisor.
527 As of September 2009, VMware has started a phased retirement
528 of this feature from VMware's products. Please see
529 feature-removal-schedule.txt for details. If you are
530 planning to enable this option, please note that you cannot
531 live migrate a VMI enabled VM to a future VMware product,
532 which doesn't support VMI. So if you expect your kernel to
533 seamlessly migrate to newer VMware products, keep this
534 disabled.
536 config KVM_CLOCK
537 bool "KVM paravirtualized clock"
538 select PARAVIRT
539 select PARAVIRT_CLOCK
540 ---help---
541 Turning on this option will allow you to run a paravirtualized clock
542 when running over the KVM hypervisor. Instead of relying on a PIT
543 (or probably other) emulation by the underlying device model, the host
544 provides the guest with timing infrastructure such as time of day, and
545 system time
547 config KVM_GUEST
548 bool "KVM Guest support"
549 select PARAVIRT
550 ---help---
551 This option enables various optimizations for running under the KVM
552 hypervisor.
554 source "arch/x86/lguest/Kconfig"
556 config PARAVIRT
557 bool "Enable paravirtualization code"
558 ---help---
559 This changes the kernel so it can modify itself when it is run
560 under a hypervisor, potentially improving performance significantly
561 over full virtualization. However, when run without a hypervisor
562 the kernel is theoretically slower and slightly larger.
564 config PARAVIRT_SPINLOCKS
565 bool "Paravirtualization layer for spinlocks"
566 depends on PARAVIRT && SMP && EXPERIMENTAL
567 ---help---
568 Paravirtualized spinlocks allow a pvops backend to replace the
569 spinlock implementation with something virtualization-friendly
570 (for example, block the virtual CPU rather than spinning).
572 Unfortunately the downside is an up to 5% performance hit on
573 native kernels, with various workloads.
575 If you are unsure how to answer this question, answer N.
577 config PARAVIRT_CLOCK
578 bool
580 endif
582 config PARAVIRT_DEBUG
583 bool "paravirt-ops debugging"
584 depends on PARAVIRT && DEBUG_KERNEL
585 ---help---
586 Enable to debug paravirt_ops internals. Specifically, BUG if
587 a paravirt_op is missing when it is called.
589 config NO_BOOTMEM
590 default y
591 bool "Disable Bootmem code"
592 ---help---
593 Use early_res directly instead of bootmem before slab is ready.
594 - allocator (buddy) [generic]
595 - early allocator (bootmem) [generic]
596 - very early allocator (reserve_early*()) [x86]
597 - very very early allocator (early brk model) [x86]
598 So reduce one layer between early allocator to final allocator
601 config MEMTEST
602 bool "Memtest"
603 ---help---
604 This option adds a kernel parameter 'memtest', which allows memtest
605 to be set.
606 memtest=0, mean disabled; -- default
607 memtest=1, mean do 1 test pattern;
608 ...
609 memtest=4, mean do 4 test patterns.
610 If you are unsure how to answer this question, answer N.
612 config X86_SUMMIT_NUMA
613 def_bool y
614 depends on X86_32 && NUMA && X86_32_NON_STANDARD
616 config X86_CYCLONE_TIMER
617 def_bool y
618 depends on X86_32_NON_STANDARD
620 source "arch/x86/Kconfig.cpu"
622 config HPET_TIMER
623 def_bool X86_64
624 prompt "HPET Timer Support" if X86_32
625 ---help---
626 Use the IA-PC HPET (High Precision Event Timer) to manage
627 time in preference to the PIT and RTC, if a HPET is
628 present.
629 HPET is the next generation timer replacing legacy 8254s.
630 The HPET provides a stable time base on SMP
631 systems, unlike the TSC, but it is more expensive to access,
632 as it is off-chip. You can find the HPET spec at
633 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
635 You can safely choose Y here. However, HPET will only be
636 activated if the platform and the BIOS support this feature.
637 Otherwise the 8254 will be used for timing services.
639 Choose N to continue using the legacy 8254 timer.
641 config HPET_EMULATE_RTC
642 def_bool y
643 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
645 config APB_TIMER
646 def_bool y if MRST
647 prompt "Langwell APB Timer Support" if X86_MRST
648 help
649 APB timer is the replacement for 8254, HPET on X86 MID platforms.
650 The APBT provides a stable time base on SMP
651 systems, unlike the TSC, but it is more expensive to access,
652 as it is off-chip. APB timers are always running regardless of CPU
653 C states, they are used as per CPU clockevent device when possible.
655 # Mark as embedded because too many people got it wrong.
656 # The code disables itself when not needed.
657 config DMI
658 default y
659 bool "Enable DMI scanning" if EMBEDDED
660 ---help---
661 Enabled scanning of DMI to identify machine quirks. Say Y
662 here unless you have verified that your setup is not
663 affected by entries in the DMI blacklist. Required by PNP
664 BIOS code.
666 config GART_IOMMU
667 bool "GART IOMMU support" if EMBEDDED
668 default y
669 select SWIOTLB
670 depends on X86_64 && PCI && K8_NB
671 ---help---
672 Support for full DMA access of devices with 32bit memory access only
673 on systems with more than 3GB. This is usually needed for USB,
674 sound, many IDE/SATA chipsets and some other devices.
675 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
676 based hardware IOMMU and a software bounce buffer based IOMMU used
677 on Intel systems and as fallback.
678 The code is only active when needed (enough memory and limited
679 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
680 too.
682 config CALGARY_IOMMU
683 bool "IBM Calgary IOMMU support"
684 select SWIOTLB
685 depends on X86_64 && PCI && EXPERIMENTAL
686 ---help---
687 Support for hardware IOMMUs in IBM's xSeries x366 and x460
688 systems. Needed to run systems with more than 3GB of memory
689 properly with 32-bit PCI devices that do not support DAC
690 (Double Address Cycle). Calgary also supports bus level
691 isolation, where all DMAs pass through the IOMMU. This
692 prevents them from going anywhere except their intended
693 destination. This catches hard-to-find kernel bugs and
694 mis-behaving drivers and devices that do not use the DMA-API
695 properly to set up their DMA buffers. The IOMMU can be
696 turned off at boot time with the iommu=off parameter.
697 Normally the kernel will make the right choice by itself.
698 If unsure, say Y.
700 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
701 def_bool y
702 prompt "Should Calgary be enabled by default?"
703 depends on CALGARY_IOMMU
704 ---help---
705 Should Calgary be enabled by default? if you choose 'y', Calgary
706 will be used (if it exists). If you choose 'n', Calgary will not be
707 used even if it exists. If you choose 'n' and would like to use
708 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
709 If unsure, say Y.
711 config AMD_IOMMU
712 bool "AMD IOMMU support"
713 select SWIOTLB
714 select PCI_MSI
715 depends on X86_64 && PCI && ACPI
716 ---help---
717 With this option you can enable support for AMD IOMMU hardware in
718 your system. An IOMMU is a hardware component which provides
719 remapping of DMA memory accesses from devices. With an AMD IOMMU you
720 can isolate the the DMA memory of different devices and protect the
721 system from misbehaving device drivers or hardware.
723 You can find out if your system has an AMD IOMMU if you look into
724 your BIOS for an option to enable it or if you have an IVRS ACPI
725 table.
727 config AMD_IOMMU_STATS
728 bool "Export AMD IOMMU statistics to debugfs"
729 depends on AMD_IOMMU
730 select DEBUG_FS
731 ---help---
732 This option enables code in the AMD IOMMU driver to collect various
733 statistics about whats happening in the driver and exports that
734 information to userspace via debugfs.
735 If unsure, say N.
737 # need this always selected by IOMMU for the VIA workaround
738 config SWIOTLB
739 def_bool y if X86_64
740 ---help---
741 Support for software bounce buffers used on x86-64 systems
742 which don't have a hardware IOMMU (e.g. the current generation
743 of Intel's x86-64 CPUs). Using this PCI devices which can only
744 access 32-bits of memory can be used on systems with more than
745 3 GB of memory. If unsure, say Y.
747 config IOMMU_HELPER
748 def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
750 config IOMMU_API
751 def_bool (AMD_IOMMU || DMAR)
753 config MAXSMP
754 bool "Configure Maximum number of SMP Processors and NUMA Nodes"
755 depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
756 select CPUMASK_OFFSTACK
757 ---help---
758 Configure maximum number of CPUS and NUMA Nodes for this architecture.
759 If unsure, say N.
761 config NR_CPUS
762 int "Maximum number of CPUs" if SMP && !MAXSMP
763 range 2 8 if SMP && X86_32 && !X86_BIGSMP
764 range 2 512 if SMP && !MAXSMP
765 default "1" if !SMP
766 default "4096" if MAXSMP
767 default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
768 default "8" if SMP
769 ---help---
770 This allows you to specify the maximum number of CPUs which this
771 kernel will support. The maximum supported value is 512 and the
772 minimum value which makes sense is 2.
774 This is purely to save memory - each supported CPU adds
775 approximately eight kilobytes to the kernel image.
777 config SCHED_SMT
778 bool "SMT (Hyperthreading) scheduler support"
779 depends on X86_HT
780 ---help---
781 SMT scheduler support improves the CPU scheduler's decision making
782 when dealing with Intel Pentium 4 chips with HyperThreading at a
783 cost of slightly increased overhead in some places. If unsure say
784 N here.
786 config SCHED_MC
787 def_bool y
788 prompt "Multi-core scheduler support"
789 depends on X86_HT
790 ---help---
791 Multi-core scheduler support improves the CPU scheduler's decision
792 making when dealing with multi-core CPU chips at a cost of slightly
793 increased overhead in some places. If unsure say N here.
795 source "kernel/Kconfig.preempt"
797 config X86_UP_APIC
798 bool "Local APIC support on uniprocessors"
799 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
800 ---help---
801 A local APIC (Advanced Programmable Interrupt Controller) is an
802 integrated interrupt controller in the CPU. If you have a single-CPU
803 system which has a processor with a local APIC, you can say Y here to
804 enable and use it. If you say Y here even though your machine doesn't
805 have a local APIC, then the kernel will still run with no slowdown at
806 all. The local APIC supports CPU-generated self-interrupts (timer,
807 performance counters), and the NMI watchdog which detects hard
808 lockups.
810 config X86_UP_IOAPIC
811 bool "IO-APIC support on uniprocessors"
812 depends on X86_UP_APIC
813 ---help---
814 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
815 SMP-capable replacement for PC-style interrupt controllers. Most
816 SMP systems and many recent uniprocessor systems have one.
818 If you have a single-CPU system with an IO-APIC, you can say Y here
819 to use it. If you say Y here even though your machine doesn't have
820 an IO-APIC, then the kernel will still run with no slowdown at all.
822 config X86_LOCAL_APIC
823 def_bool y
824 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
826 config X86_IO_APIC
827 def_bool y
828 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
830 config X86_VISWS_APIC
831 def_bool y
832 depends on X86_32 && X86_VISWS
834 config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
835 bool "Reroute for broken boot IRQs"
836 depends on X86_IO_APIC
837 ---help---
838 This option enables a workaround that fixes a source of
839 spurious interrupts. This is recommended when threaded
840 interrupt handling is used on systems where the generation of
841 superfluous "boot interrupts" cannot be disabled.
843 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
844 entry in the chipset's IO-APIC is masked (as, e.g. the RT
845 kernel does during interrupt handling). On chipsets where this
846 boot IRQ generation cannot be disabled, this workaround keeps
847 the original IRQ line masked so that only the equivalent "boot
848 IRQ" is delivered to the CPUs. The workaround also tells the
849 kernel to set up the IRQ handler on the boot IRQ line. In this
850 way only one interrupt is delivered to the kernel. Otherwise
851 the spurious second interrupt may cause the kernel to bring
852 down (vital) interrupt lines.
854 Only affects "broken" chipsets. Interrupt sharing may be
855 increased on these systems.
857 config X86_MCE
858 bool "Machine Check / overheating reporting"
859 ---help---
860 Machine Check support allows the processor to notify the
861 kernel if it detects a problem (e.g. overheating, data corruption).
862 The action the kernel takes depends on the severity of the problem,
863 ranging from warning messages to halting the machine.
865 config X86_MCE_INTEL
866 def_bool y
867 prompt "Intel MCE features"
868 depends on X86_MCE && X86_LOCAL_APIC
869 ---help---
870 Additional support for intel specific MCE features such as
871 the thermal monitor.
873 config X86_MCE_AMD
874 def_bool y
875 prompt "AMD MCE features"
876 depends on X86_MCE && X86_LOCAL_APIC
877 ---help---
878 Additional support for AMD specific MCE features such as
879 the DRAM Error Threshold.
881 config X86_ANCIENT_MCE
882 bool "Support for old Pentium 5 / WinChip machine checks"
883 depends on X86_32 && X86_MCE
884 ---help---
885 Include support for machine check handling on old Pentium 5 or WinChip
886 systems. These typically need to be enabled explicitely on the command
887 line.
889 config X86_MCE_THRESHOLD
890 depends on X86_MCE_AMD || X86_MCE_INTEL
891 def_bool y
893 config X86_MCE_INJECT
894 depends on X86_MCE
895 tristate "Machine check injector support"
896 ---help---
897 Provide support for injecting machine checks for testing purposes.
898 If you don't know what a machine check is and you don't do kernel
899 QA it is safe to say n.
901 config X86_THERMAL_VECTOR
902 def_bool y
903 depends on X86_MCE_INTEL
905 config VM86
906 bool "Enable VM86 support" if EMBEDDED
907 default y
908 depends on X86_32
909 ---help---
910 This option is required by programs like DOSEMU to run 16-bit legacy
911 code on X86 processors. It also may be needed by software like
912 XFree86 to initialize some video cards via BIOS. Disabling this
913 option saves about 6k.
915 config TOSHIBA
916 tristate "Toshiba Laptop support"
917 depends on X86_32
918 ---help---
919 This adds a driver to safely access the System Management Mode of
920 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
921 not work on models with a Phoenix BIOS. The System Management Mode
922 is used to set the BIOS and power saving options on Toshiba portables.
924 For information on utilities to make use of this driver see the
925 Toshiba Linux utilities web site at:
926 <http://www.buzzard.org.uk/toshiba/>.
928 Say Y if you intend to run this kernel on a Toshiba portable.
929 Say N otherwise.
931 config I8K
932 tristate "Dell laptop support"
933 ---help---
934 This adds a driver to safely access the System Management Mode
935 of the CPU on the Dell Inspiron 8000. The System Management Mode
936 is used to read cpu temperature and cooling fan status and to
937 control the fans on the I8K portables.
939 This driver has been tested only on the Inspiron 8000 but it may
940 also work with other Dell laptops. You can force loading on other
941 models by passing the parameter `force=1' to the module. Use at
942 your own risk.
944 For information on utilities to make use of this driver see the
945 I8K Linux utilities web site at:
946 <http://people.debian.org/~dz/i8k/>
948 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
949 Say N otherwise.
951 config X86_REBOOTFIXUPS
952 bool "Enable X86 board specific fixups for reboot"
953 depends on X86_32
954 ---help---
955 This enables chipset and/or board specific fixups to be done
956 in order to get reboot to work correctly. This is only needed on
957 some combinations of hardware and BIOS. The symptom, for which
958 this config is intended, is when reboot ends with a stalled/hung
959 system.
961 Currently, the only fixup is for the Geode machines using
962 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
964 Say Y if you want to enable the fixup. Currently, it's safe to
965 enable this option even if you don't need it.
966 Say N otherwise.
968 config MICROCODE
969 tristate "/dev/cpu/microcode - microcode support"
970 select FW_LOADER
971 ---help---
972 If you say Y here, you will be able to update the microcode on
973 certain Intel and AMD processors. The Intel support is for the
974 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III,
975 Pentium 4, Xeon etc. The AMD support is for family 0x10 and
976 0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra.
977 You will obviously need the actual microcode binary data itself
978 which is not shipped with the Linux kernel.
980 This option selects the general module only, you need to select
981 at least one vendor specific module as well.
983 To compile this driver as a module, choose M here: the
984 module will be called microcode.
986 config MICROCODE_INTEL
987 bool "Intel microcode patch loading support"
988 depends on MICROCODE
989 default MICROCODE
990 select FW_LOADER
991 ---help---
992 This options enables microcode patch loading support for Intel
993 processors.
995 For latest news and information on obtaining all the required
996 Intel ingredients for this driver, check:
997 <http://www.urbanmyth.org/microcode/>.
999 config MICROCODE_AMD
1000 bool "AMD microcode patch loading support"
1001 depends on MICROCODE
1002 select FW_LOADER
1003 ---help---
1004 If you select this option, microcode patch loading support for AMD
1005 processors will be enabled.
1007 config MICROCODE_OLD_INTERFACE
1008 def_bool y
1009 depends on MICROCODE
1011 config X86_MSR
1012 tristate "/dev/cpu/*/msr - Model-specific register support"
1013 ---help---
1014 This device gives privileged processes access to the x86
1015 Model-Specific Registers (MSRs). It is a character device with
1016 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1017 MSR accesses are directed to a specific CPU on multi-processor
1018 systems.
1020 config X86_CPUID
1021 tristate "/dev/cpu/*/cpuid - CPU information support"
1022 ---help---
1023 This device gives processes access to the x86 CPUID instruction to
1024 be executed on a specific processor. It is a character device
1025 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1026 /dev/cpu/31/cpuid.
1028 choice
1029 prompt "High Memory Support"
1030 default HIGHMEM64G if X86_NUMAQ
1031 default HIGHMEM4G
1032 depends on X86_32
1034 config NOHIGHMEM
1035 bool "off"
1036 depends on !X86_NUMAQ
1037 ---help---
1038 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1039 However, the address space of 32-bit x86 processors is only 4
1040 Gigabytes large. That means that, if you have a large amount of
1041 physical memory, not all of it can be "permanently mapped" by the
1042 kernel. The physical memory that's not permanently mapped is called
1043 "high memory".
1045 If you are compiling a kernel which will never run on a machine with
1046 more than 1 Gigabyte total physical RAM, answer "off" here (default
1047 choice and suitable for most users). This will result in a "3GB/1GB"
1048 split: 3GB are mapped so that each process sees a 3GB virtual memory
1049 space and the remaining part of the 4GB virtual memory space is used
1050 by the kernel to permanently map as much physical memory as
1051 possible.
1053 If the machine has between 1 and 4 Gigabytes physical RAM, then
1054 answer "4GB" here.
1056 If more than 4 Gigabytes is used then answer "64GB" here. This
1057 selection turns Intel PAE (Physical Address Extension) mode on.
1058 PAE implements 3-level paging on IA32 processors. PAE is fully
1059 supported by Linux, PAE mode is implemented on all recent Intel
1060 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1061 then the kernel will not boot on CPUs that don't support PAE!
1063 The actual amount of total physical memory will either be
1064 auto detected or can be forced by using a kernel command line option
1065 such as "mem=256M". (Try "man bootparam" or see the documentation of
1066 your boot loader (lilo or loadlin) about how to pass options to the
1067 kernel at boot time.)
1069 If unsure, say "off".
1071 config HIGHMEM4G
1072 bool "4GB"
1073 depends on !X86_NUMAQ
1074 ---help---
1075 Select this if you have a 32-bit processor and between 1 and 4
1076 gigabytes of physical RAM.
1078 config HIGHMEM64G
1079 bool "64GB"
1080 depends on !M386 && !M486
1081 select X86_PAE
1082 ---help---
1083 Select this if you have a 32-bit processor and more than 4
1084 gigabytes of physical RAM.
1086 endchoice
1088 choice
1089 depends on EXPERIMENTAL
1090 prompt "Memory split" if EMBEDDED
1091 default VMSPLIT_3G
1092 depends on X86_32
1093 ---help---
1094 Select the desired split between kernel and user memory.
1096 If the address range available to the kernel is less than the
1097 physical memory installed, the remaining memory will be available
1098 as "high memory". Accessing high memory is a little more costly
1099 than low memory, as it needs to be mapped into the kernel first.
1100 Note that increasing the kernel address space limits the range
1101 available to user programs, making the address space there
1102 tighter. Selecting anything other than the default 3G/1G split
1103 will also likely make your kernel incompatible with binary-only
1104 kernel modules.
1106 If you are not absolutely sure what you are doing, leave this
1107 option alone!
1109 config VMSPLIT_3G
1110 bool "3G/1G user/kernel split"
1111 config VMSPLIT_3G_OPT
1112 depends on !X86_PAE
1113 bool "3G/1G user/kernel split (for full 1G low memory)"
1114 config VMSPLIT_2G
1115 bool "2G/2G user/kernel split"
1116 config VMSPLIT_2G_OPT
1117 depends on !X86_PAE
1118 bool "2G/2G user/kernel split (for full 2G low memory)"
1119 config VMSPLIT_1G
1120 bool "1G/3G user/kernel split"
1121 endchoice
1123 config PAGE_OFFSET
1124 hex
1125 default 0xB0000000 if VMSPLIT_3G_OPT
1126 default 0x80000000 if VMSPLIT_2G
1127 default 0x78000000 if VMSPLIT_2G_OPT
1128 default 0x40000000 if VMSPLIT_1G
1129 default 0xC0000000
1130 depends on X86_32
1132 config HIGHMEM
1133 def_bool y
1134 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1136 config X86_PAE
1137 bool "PAE (Physical Address Extension) Support"
1138 depends on X86_32 && !HIGHMEM4G
1139 ---help---
1140 PAE is required for NX support, and furthermore enables
1141 larger swapspace support for non-overcommit purposes. It
1142 has the cost of more pagetable lookup overhead, and also
1143 consumes more pagetable space per process.
1145 config ARCH_PHYS_ADDR_T_64BIT
1146 def_bool X86_64 || X86_PAE
1148 config DIRECT_GBPAGES
1149 bool "Enable 1GB pages for kernel pagetables" if EMBEDDED
1150 default y
1151 depends on X86_64
1152 ---help---
1153 Allow the kernel linear mapping to use 1GB pages on CPUs that
1154 support it. This can improve the kernel's performance a tiny bit by
1155 reducing TLB pressure. If in doubt, say "Y".
1157 # Common NUMA Features
1158 config NUMA
1159 bool "Numa Memory Allocation and Scheduler Support"
1160 depends on SMP
1161 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
1162 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
1163 ---help---
1164 Enable NUMA (Non Uniform Memory Access) support.
1166 The kernel will try to allocate memory used by a CPU on the
1167 local memory controller of the CPU and add some more
1168 NUMA awareness to the kernel.
1170 For 64-bit this is recommended if the system is Intel Core i7
1171 (or later), AMD Opteron, or EM64T NUMA.
1173 For 32-bit this is only needed on (rare) 32-bit-only platforms
1174 that support NUMA topologies, such as NUMAQ / Summit, or if you
1175 boot a 32-bit kernel on a 64-bit NUMA platform.
1177 Otherwise, you should say N.
1179 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
1180 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
1182 config K8_NUMA
1183 def_bool y
1184 prompt "Old style AMD Opteron NUMA detection"
1185 depends on X86_64 && NUMA && PCI
1186 ---help---
1187 Enable K8 NUMA node topology detection. You should say Y here if
1188 you have a multi processor AMD K8 system. This uses an old
1189 method to read the NUMA configuration directly from the builtin
1190 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
1191 instead, which also takes priority if both are compiled in.
1193 config X86_64_ACPI_NUMA
1194 def_bool y
1195 prompt "ACPI NUMA detection"
1196 depends on X86_64 && NUMA && ACPI && PCI
1197 select ACPI_NUMA
1198 ---help---
1199 Enable ACPI SRAT based node topology detection.
1201 # Some NUMA nodes have memory ranges that span
1202 # other nodes. Even though a pfn is valid and
1203 # between a node's start and end pfns, it may not
1204 # reside on that node. See memmap_init_zone()
1205 # for details.
1206 config NODES_SPAN_OTHER_NODES
1207 def_bool y
1208 depends on X86_64_ACPI_NUMA
1210 config NUMA_EMU
1211 bool "NUMA emulation"
1212 depends on X86_64 && NUMA
1213 ---help---
1214 Enable NUMA emulation. A flat machine will be split
1215 into virtual nodes when booted with "numa=fake=N", where N is the
1216 number of nodes. This is only useful for debugging.
1218 config NODES_SHIFT
1219 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1220 range 1 10
1221 default "10" if MAXSMP
1222 default "6" if X86_64
1223 default "4" if X86_NUMAQ
1224 default "3"
1225 depends on NEED_MULTIPLE_NODES
1226 ---help---
1227 Specify the maximum number of NUMA Nodes available on the target
1228 system. Increases memory reserved to accommodate various tables.
1230 config HAVE_ARCH_BOOTMEM
1231 def_bool y
1232 depends on X86_32 && NUMA
1234 config ARCH_HAVE_MEMORY_PRESENT
1235 def_bool y
1236 depends on X86_32 && DISCONTIGMEM
1238 config NEED_NODE_MEMMAP_SIZE
1239 def_bool y
1240 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1242 config HAVE_ARCH_ALLOC_REMAP
1243 def_bool y
1244 depends on X86_32 && NUMA
1246 config ARCH_FLATMEM_ENABLE
1247 def_bool y
1248 depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && !NUMA
1250 config ARCH_DISCONTIGMEM_ENABLE
1251 def_bool y
1252 depends on NUMA && X86_32
1254 config ARCH_DISCONTIGMEM_DEFAULT
1255 def_bool y
1256 depends on NUMA && X86_32
1258 config ARCH_PROC_KCORE_TEXT
1259 def_bool y
1260 depends on X86_64 && PROC_KCORE
1262 config ARCH_SPARSEMEM_DEFAULT
1263 def_bool y
1264 depends on X86_64
1266 config ARCH_SPARSEMEM_ENABLE
1267 def_bool y
1268 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD
1269 select SPARSEMEM_STATIC if X86_32
1270 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1272 config ARCH_SELECT_MEMORY_MODEL
1273 def_bool y
1274 depends on ARCH_SPARSEMEM_ENABLE
1276 config ARCH_MEMORY_PROBE
1277 def_bool X86_64
1278 depends on MEMORY_HOTPLUG
1280 config ILLEGAL_POINTER_VALUE
1281 hex
1282 default 0 if X86_32
1283 default 0xdead000000000000 if X86_64
1285 source "mm/Kconfig"
1287 config HIGHPTE
1288 bool "Allocate 3rd-level pagetables from highmem"
1289 depends on HIGHMEM
1290 ---help---
1291 The VM uses one page table entry for each page of physical memory.
1292 For systems with a lot of RAM, this can be wasteful of precious
1293 low memory. Setting this option will put user-space page table
1294 entries in high memory.
1296 config X86_CHECK_BIOS_CORRUPTION
1297 bool "Check for low memory corruption"
1298 ---help---
1299 Periodically check for memory corruption in low memory, which
1300 is suspected to be caused by BIOS. Even when enabled in the
1301 configuration, it is disabled at runtime. Enable it by
1302 setting "memory_corruption_check=1" on the kernel command
1303 line. By default it scans the low 64k of memory every 60
1304 seconds; see the memory_corruption_check_size and
1305 memory_corruption_check_period parameters in
1306 Documentation/kernel-parameters.txt to adjust this.
1308 When enabled with the default parameters, this option has
1309 almost no overhead, as it reserves a relatively small amount
1310 of memory and scans it infrequently. It both detects corruption
1311 and prevents it from affecting the running system.
1313 It is, however, intended as a diagnostic tool; if repeatable
1314 BIOS-originated corruption always affects the same memory,
1315 you can use memmap= to prevent the kernel from using that
1316 memory.
1318 config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1319 bool "Set the default setting of memory_corruption_check"
1320 depends on X86_CHECK_BIOS_CORRUPTION
1321 default y
1322 ---help---
1323 Set whether the default state of memory_corruption_check is
1324 on or off.
1326 config X86_RESERVE_LOW_64K
1327 bool "Reserve low 64K of RAM on AMI/Phoenix BIOSen"
1328 default y
1329 ---help---
1330 Reserve the first 64K of physical RAM on BIOSes that are known
1331 to potentially corrupt that memory range. A numbers of BIOSes are
1332 known to utilize this area during suspend/resume, so it must not
1333 be used by the kernel.
1335 Set this to N if you are absolutely sure that you trust the BIOS
1336 to get all its memory reservations and usages right.
1338 If you have doubts about the BIOS (e.g. suspend/resume does not
1339 work or there's kernel crashes after certain hardware hotplug
1340 events) and it's not AMI or Phoenix, then you might want to enable
1341 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check typical
1342 corruption patterns.
1344 Say Y if unsure.
1346 config MATH_EMULATION
1347 bool
1348 prompt "Math emulation" if X86_32
1349 ---help---
1350 Linux can emulate a math coprocessor (used for floating point
1351 operations) if you don't have one. 486DX and Pentium processors have
1352 a math coprocessor built in, 486SX and 386 do not, unless you added
1353 a 487DX or 387, respectively. (The messages during boot time can
1354 give you some hints here ["man dmesg"].) Everyone needs either a
1355 coprocessor or this emulation.
1357 If you don't have a math coprocessor, you need to say Y here; if you
1358 say Y here even though you have a coprocessor, the coprocessor will
1359 be used nevertheless. (This behavior can be changed with the kernel
1360 command line option "no387", which comes handy if your coprocessor
1361 is broken. Try "man bootparam" or see the documentation of your boot
1362 loader (lilo or loadlin) about how to pass options to the kernel at
1363 boot time.) This means that it is a good idea to say Y here if you
1364 intend to use this kernel on different machines.
1366 More information about the internals of the Linux math coprocessor
1367 emulation can be found in <file:arch/x86/math-emu/README>.
1369 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1370 kernel, it won't hurt.
1372 config MTRR
1373 def_bool y
1374 prompt "MTRR (Memory Type Range Register) support" if EMBEDDED
1375 ---help---
1376 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1377 the Memory Type Range Registers (MTRRs) may be used to control
1378 processor access to memory ranges. This is most useful if you have
1379 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1380 allows bus write transfers to be combined into a larger transfer
1381 before bursting over the PCI/AGP bus. This can increase performance
1382 of image write operations 2.5 times or more. Saying Y here creates a
1383 /proc/mtrr file which may be used to manipulate your processor's
1384 MTRRs. Typically the X server should use this.
1386 This code has a reasonably generic interface so that similar
1387 control registers on other processors can be easily supported
1388 as well:
1390 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1391 Registers (ARRs) which provide a similar functionality to MTRRs. For
1392 these, the ARRs are used to emulate the MTRRs.
1393 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1394 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1395 write-combining. All of these processors are supported by this code
1396 and it makes sense to say Y here if you have one of them.
1398 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1399 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1400 can lead to all sorts of problems, so it's good to say Y here.
1402 You can safely say Y even if your machine doesn't have MTRRs, you'll
1403 just add about 9 KB to your kernel.
1405 See <file:Documentation/x86/mtrr.txt> for more information.
1407 config MTRR_SANITIZER
1408 def_bool y
1409 prompt "MTRR cleanup support"
1410 depends on MTRR
1411 ---help---
1412 Convert MTRR layout from continuous to discrete, so X drivers can
1413 add writeback entries.
1415 Can be disabled with disable_mtrr_cleanup on the kernel command line.
1416 The largest mtrr entry size for a continuous block can be set with
1417 mtrr_chunk_size.
1419 If unsure, say Y.
1421 config MTRR_SANITIZER_ENABLE_DEFAULT
1422 int "MTRR cleanup enable value (0-1)"
1423 range 0 1
1424 default "0"
1425 depends on MTRR_SANITIZER
1426 ---help---
1427 Enable mtrr cleanup default value
1429 config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1430 int "MTRR cleanup spare reg num (0-7)"
1431 range 0 7
1432 default "1"
1433 depends on MTRR_SANITIZER
1434 ---help---
1435 mtrr cleanup spare entries default, it can be changed via
1436 mtrr_spare_reg_nr=N on the kernel command line.
1438 config X86_PAT
1439 def_bool y
1440 prompt "x86 PAT support" if EMBEDDED
1441 depends on MTRR
1442 ---help---
1443 Use PAT attributes to setup page level cache control.
1445 PATs are the modern equivalents of MTRRs and are much more
1446 flexible than MTRRs.
1448 Say N here if you see bootup problems (boot crash, boot hang,
1449 spontaneous reboots) or a non-working video driver.
1451 If unsure, say Y.
1453 config ARCH_USES_PG_UNCACHED
1454 def_bool y
1455 depends on X86_PAT
1457 config EFI
1458 bool "EFI runtime service support"
1459 depends on ACPI
1460 ---help---
1461 This enables the kernel to use EFI runtime services that are
1462 available (such as the EFI variable services).
1464 This option is only useful on systems that have EFI firmware.
1465 In addition, you should use the latest ELILO loader available
1466 at <http://elilo.sourceforge.net> in order to take advantage
1467 of EFI runtime services. However, even with this option, the
1468 resultant kernel should continue to boot on existing non-EFI
1469 platforms.
1471 config SECCOMP
1472 def_bool y
1473 prompt "Enable seccomp to safely compute untrusted bytecode"
1474 ---help---
1475 This kernel feature is useful for number crunching applications
1476 that may need to compute untrusted bytecode during their
1477 execution. By using pipes or other transports made available to
1478 the process as file descriptors supporting the read/write
1479 syscalls, it's possible to isolate those applications in
1480 their own address space using seccomp. Once seccomp is
1481 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1482 and the task is only allowed to execute a few safe syscalls
1483 defined by each seccomp mode.
1485 If unsure, say Y. Only embedded should say N here.
1487 config CC_STACKPROTECTOR
1488 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
1489 ---help---
1490 This option turns on the -fstack-protector GCC feature. This
1491 feature puts, at the beginning of functions, a canary value on
1492 the stack just before the return address, and validates
1493 the value just before actually returning. Stack based buffer
1494 overflows (that need to overwrite this return address) now also
1495 overwrite the canary, which gets detected and the attack is then
1496 neutralized via a kernel panic.
1498 This feature requires gcc version 4.2 or above, or a distribution
1499 gcc with the feature backported. Older versions are automatically
1500 detected and for those versions, this configuration option is
1501 ignored. (and a warning is printed during bootup)
1503 source kernel/Kconfig.hz
1505 config KEXEC
1506 bool "kexec system call"
1507 ---help---
1508 kexec is a system call that implements the ability to shutdown your
1509 current kernel, and to start another kernel. It is like a reboot
1510 but it is independent of the system firmware. And like a reboot
1511 you can start any kernel with it, not just Linux.
1513 The name comes from the similarity to the exec system call.
1515 It is an ongoing process to be certain the hardware in a machine
1516 is properly shutdown, so do not be surprised if this code does not
1517 initially work for you. It may help to enable device hotplugging
1518 support. As of this writing the exact hardware interface is
1519 strongly in flux, so no good recommendation can be made.
1521 config CRASH_DUMP
1522 bool "kernel crash dumps"
1523 depends on X86_64 || (X86_32 && HIGHMEM)
1524 ---help---
1525 Generate crash dump after being started by kexec.
1526 This should be normally only set in special crash dump kernels
1527 which are loaded in the main kernel with kexec-tools into
1528 a specially reserved region and then later executed after
1529 a crash by kdump/kexec. The crash dump kernel must be compiled
1530 to a memory address not used by the main kernel or BIOS using
1531 PHYSICAL_START, or it must be built as a relocatable image
1532 (CONFIG_RELOCATABLE=y).
1533 For more details see Documentation/kdump/kdump.txt
1535 config KEXEC_JUMP
1536 bool "kexec jump (EXPERIMENTAL)"
1537 depends on EXPERIMENTAL
1538 depends on KEXEC && HIBERNATION
1539 ---help---
1540 Jump between original kernel and kexeced kernel and invoke
1541 code in physical address mode via KEXEC
1543 config PHYSICAL_START
1544 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
1545 default "0x1000000"
1546 ---help---
1547 This gives the physical address where the kernel is loaded.
1549 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1550 bzImage will decompress itself to above physical address and
1551 run from there. Otherwise, bzImage will run from the address where
1552 it has been loaded by the boot loader and will ignore above physical
1553 address.
1555 In normal kdump cases one does not have to set/change this option
1556 as now bzImage can be compiled as a completely relocatable image
1557 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1558 address. This option is mainly useful for the folks who don't want
1559 to use a bzImage for capturing the crash dump and want to use a
1560 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1561 to be specifically compiled to run from a specific memory area
1562 (normally a reserved region) and this option comes handy.
1564 So if you are using bzImage for capturing the crash dump,
1565 leave the value here unchanged to 0x1000000 and set
1566 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
1567 for capturing the crash dump change this value to start of
1568 the reserved region. In other words, it can be set based on
1569 the "X" value as specified in the "crashkernel=YM@XM"
1570 command line boot parameter passed to the panic-ed
1571 kernel. Please take a look at Documentation/kdump/kdump.txt
1572 for more details about crash dumps.
1574 Usage of bzImage for capturing the crash dump is recommended as
1575 one does not have to build two kernels. Same kernel can be used
1576 as production kernel and capture kernel. Above option should have
1577 gone away after relocatable bzImage support is introduced. But it
1578 is present because there are users out there who continue to use
1579 vmlinux for dump capture. This option should go away down the
1580 line.
1582 Don't change this unless you know what you are doing.
1584 config RELOCATABLE
1585 bool "Build a relocatable kernel"
1586 default y
1587 ---help---
1588 This builds a kernel image that retains relocation information
1589 so it can be loaded someplace besides the default 1MB.
1590 The relocations tend to make the kernel binary about 10% larger,
1591 but are discarded at runtime.
1593 One use is for the kexec on panic case where the recovery kernel
1594 must live at a different physical address than the primary
1595 kernel.
1597 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1598 it has been loaded at and the compile time physical address
1599 (CONFIG_PHYSICAL_START) is ignored.
1601 # Relocation on x86-32 needs some additional build support
1602 config X86_NEED_RELOCS
1603 def_bool y
1604 depends on X86_32 && RELOCATABLE
1606 config PHYSICAL_ALIGN
1607 hex "Alignment value to which kernel should be aligned" if X86_32
1608 default "0x1000000"
1609 range 0x2000 0x1000000
1610 ---help---
1611 This value puts the alignment restrictions on physical address
1612 where kernel is loaded and run from. Kernel is compiled for an
1613 address which meets above alignment restriction.
1615 If bootloader loads the kernel at a non-aligned address and
1616 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1617 address aligned to above value and run from there.
1619 If bootloader loads the kernel at a non-aligned address and
1620 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1621 load address and decompress itself to the address it has been
1622 compiled for and run from there. The address for which kernel is
1623 compiled already meets above alignment restrictions. Hence the
1624 end result is that kernel runs from a physical address meeting
1625 above alignment restrictions.
1627 Don't change this unless you know what you are doing.
1629 config HOTPLUG_CPU
1630 bool "Support for hot-pluggable CPUs"
1631 depends on SMP && HOTPLUG
1632 ---help---
1633 Say Y here to allow turning CPUs off and on. CPUs can be
1634 controlled through /sys/devices/system/cpu.
1635 ( Note: power management support will enable this option
1636 automatically on SMP systems. )
1637 Say N if you want to disable CPU hotplug.
1639 config COMPAT_VDSO
1640 def_bool y
1641 prompt "Compat VDSO support"
1642 depends on X86_32 || IA32_EMULATION
1643 ---help---
1644 Map the 32-bit VDSO to the predictable old-style address too.
1646 Say N here if you are running a sufficiently recent glibc
1647 version (2.3.3 or later), to remove the high-mapped
1648 VDSO mapping and to exclusively use the randomized VDSO.
1650 If unsure, say Y.
1652 config CMDLINE_BOOL
1653 bool "Built-in kernel command line"
1654 ---help---
1655 Allow for specifying boot arguments to the kernel at
1656 build time. On some systems (e.g. embedded ones), it is
1657 necessary or convenient to provide some or all of the
1658 kernel boot arguments with the kernel itself (that is,
1659 to not rely on the boot loader to provide them.)
1661 To compile command line arguments into the kernel,
1662 set this option to 'Y', then fill in the
1663 the boot arguments in CONFIG_CMDLINE.
1665 Systems with fully functional boot loaders (i.e. non-embedded)
1666 should leave this option set to 'N'.
1668 config CMDLINE
1669 string "Built-in kernel command string"
1670 depends on CMDLINE_BOOL
1671 default ""
1672 ---help---
1673 Enter arguments here that should be compiled into the kernel
1674 image and used at boot time. If the boot loader provides a
1675 command line at boot time, it is appended to this string to
1676 form the full kernel command line, when the system boots.
1678 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
1679 change this behavior.
1681 In most cases, the command line (whether built-in or provided
1682 by the boot loader) should specify the device for the root
1683 file system.
1685 config CMDLINE_OVERRIDE
1686 bool "Built-in command line overrides boot loader arguments"
1687 depends on CMDLINE_BOOL
1688 ---help---
1689 Set this option to 'Y' to have the kernel ignore the boot loader
1690 command line, and use ONLY the built-in command line.
1692 This is used to work around broken boot loaders. This should
1693 be set to 'N' under normal conditions.
1695 endmenu
1697 config ARCH_ENABLE_MEMORY_HOTPLUG
1698 def_bool y
1699 depends on X86_64 || (X86_32 && HIGHMEM)
1701 config ARCH_ENABLE_MEMORY_HOTREMOVE
1702 def_bool y
1703 depends on MEMORY_HOTPLUG
1705 config HAVE_ARCH_EARLY_PFN_TO_NID
1706 def_bool X86_64
1707 depends on NUMA
1709 config USE_PERCPU_NUMA_NODE_ID
1710 def_bool X86_64
1711 depends on NUMA
1713 menu "Power management and ACPI options"
1715 config ARCH_HIBERNATION_HEADER
1716 def_bool y
1717 depends on X86_64 && HIBERNATION
1719 source "kernel/power/Kconfig"
1721 source "drivers/acpi/Kconfig"
1723 source "drivers/sfi/Kconfig"
1725 config X86_APM_BOOT
1726 def_bool y
1727 depends on APM || APM_MODULE
1729 menuconfig APM
1730 tristate "APM (Advanced Power Management) BIOS support"
1731 depends on X86_32 && PM_SLEEP
1732 ---help---
1733 APM is a BIOS specification for saving power using several different
1734 techniques. This is mostly useful for battery powered laptops with
1735 APM compliant BIOSes. If you say Y here, the system time will be
1736 reset after a RESUME operation, the /proc/apm device will provide
1737 battery status information, and user-space programs will receive
1738 notification of APM "events" (e.g. battery status change).
1740 If you select "Y" here, you can disable actual use of the APM
1741 BIOS by passing the "apm=off" option to the kernel at boot time.
1743 Note that the APM support is almost completely disabled for
1744 machines with more than one CPU.
1746 In order to use APM, you will need supporting software. For location
1747 and more information, read <file:Documentation/power/pm.txt> and the
1748 Battery Powered Linux mini-HOWTO, available from
1749 <http://www.tldp.org/docs.html#howto>.
1751 This driver does not spin down disk drives (see the hdparm(8)
1752 manpage ("man 8 hdparm") for that), and it doesn't turn off
1753 VESA-compliant "green" monitors.
1755 This driver does not support the TI 4000M TravelMate and the ACER
1756 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1757 desktop machines also don't have compliant BIOSes, and this driver
1758 may cause those machines to panic during the boot phase.
1760 Generally, if you don't have a battery in your machine, there isn't
1761 much point in using this driver and you should say N. If you get
1762 random kernel OOPSes or reboots that don't seem to be related to
1763 anything, try disabling/enabling this option (or disabling/enabling
1764 APM in your BIOS).
1766 Some other things you should try when experiencing seemingly random,
1767 "weird" problems:
1769 1) make sure that you have enough swap space and that it is
1770 enabled.
1771 2) pass the "no-hlt" option to the kernel
1772 3) switch on floating point emulation in the kernel and pass
1773 the "no387" option to the kernel
1774 4) pass the "floppy=nodma" option to the kernel
1775 5) pass the "mem=4M" option to the kernel (thereby disabling
1776 all but the first 4 MB of RAM)
1777 6) make sure that the CPU is not over clocked.
1778 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1779 8) disable the cache from your BIOS settings
1780 9) install a fan for the video card or exchange video RAM
1781 10) install a better fan for the CPU
1782 11) exchange RAM chips
1783 12) exchange the motherboard.
1785 To compile this driver as a module, choose M here: the
1786 module will be called apm.
1788 if APM
1790 config APM_IGNORE_USER_SUSPEND
1791 bool "Ignore USER SUSPEND"
1792 ---help---
1793 This option will ignore USER SUSPEND requests. On machines with a
1794 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1795 series notebooks, it is necessary to say Y because of a BIOS bug.
1797 config APM_DO_ENABLE
1798 bool "Enable PM at boot time"
1799 ---help---
1800 Enable APM features at boot time. From page 36 of the APM BIOS
1801 specification: "When disabled, the APM BIOS does not automatically
1802 power manage devices, enter the Standby State, enter the Suspend
1803 State, or take power saving steps in response to CPU Idle calls."
1804 This driver will make CPU Idle calls when Linux is idle (unless this
1805 feature is turned off -- see "Do CPU IDLE calls", below). This
1806 should always save battery power, but more complicated APM features
1807 will be dependent on your BIOS implementation. You may need to turn
1808 this option off if your computer hangs at boot time when using APM
1809 support, or if it beeps continuously instead of suspending. Turn
1810 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1811 T400CDT. This is off by default since most machines do fine without
1812 this feature.
1814 config APM_CPU_IDLE
1815 bool "Make CPU Idle calls when idle"
1816 ---help---
1817 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1818 On some machines, this can activate improved power savings, such as
1819 a slowed CPU clock rate, when the machine is idle. These idle calls
1820 are made after the idle loop has run for some length of time (e.g.,
1821 333 mS). On some machines, this will cause a hang at boot time or
1822 whenever the CPU becomes idle. (On machines with more than one CPU,
1823 this option does nothing.)
1825 config APM_DISPLAY_BLANK
1826 bool "Enable console blanking using APM"
1827 ---help---
1828 Enable console blanking using the APM. Some laptops can use this to
1829 turn off the LCD backlight when the screen blanker of the Linux
1830 virtual console blanks the screen. Note that this is only used by
1831 the virtual console screen blanker, and won't turn off the backlight
1832 when using the X Window system. This also doesn't have anything to
1833 do with your VESA-compliant power-saving monitor. Further, this
1834 option doesn't work for all laptops -- it might not turn off your
1835 backlight at all, or it might print a lot of errors to the console,
1836 especially if you are using gpm.
1838 config APM_ALLOW_INTS
1839 bool "Allow interrupts during APM BIOS calls"
1840 ---help---
1841 Normally we disable external interrupts while we are making calls to
1842 the APM BIOS as a measure to lessen the effects of a badly behaving
1843 BIOS implementation. The BIOS should reenable interrupts if it
1844 needs to. Unfortunately, some BIOSes do not -- especially those in
1845 many of the newer IBM Thinkpads. If you experience hangs when you
1846 suspend, try setting this to Y. Otherwise, say N.
1848 endif # APM
1850 source "arch/x86/kernel/cpu/cpufreq/Kconfig"
1852 source "drivers/cpuidle/Kconfig"
1854 source "drivers/idle/Kconfig"
1856 endmenu
1859 menu "Bus options (PCI etc.)"
1861 config PCI
1862 bool "PCI support"
1863 default y
1864 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
1865 ---help---
1866 Find out whether you have a PCI motherboard. PCI is the name of a
1867 bus system, i.e. the way the CPU talks to the other stuff inside
1868 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1869 VESA. If you have PCI, say Y, otherwise N.
1871 choice
1872 prompt "PCI access mode"
1873 depends on X86_32 && PCI
1874 default PCI_GOANY
1875 ---help---
1876 On PCI systems, the BIOS can be used to detect the PCI devices and
1877 determine their configuration. However, some old PCI motherboards
1878 have BIOS bugs and may crash if this is done. Also, some embedded
1879 PCI-based systems don't have any BIOS at all. Linux can also try to
1880 detect the PCI hardware directly without using the BIOS.
1882 With this option, you can specify how Linux should detect the
1883 PCI devices. If you choose "BIOS", the BIOS will be used,
1884 if you choose "Direct", the BIOS won't be used, and if you
1885 choose "MMConfig", then PCI Express MMCONFIG will be used.
1886 If you choose "Any", the kernel will try MMCONFIG, then the
1887 direct access method and falls back to the BIOS if that doesn't
1888 work. If unsure, go with the default, which is "Any".
1890 config PCI_GOBIOS
1891 bool "BIOS"
1893 config PCI_GOMMCONFIG
1894 bool "MMConfig"
1896 config PCI_GODIRECT
1897 bool "Direct"
1899 config PCI_GOOLPC
1900 bool "OLPC"
1901 depends on OLPC
1903 config PCI_GOANY
1904 bool "Any"
1906 endchoice
1908 config PCI_BIOS
1909 def_bool y
1910 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
1912 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1913 config PCI_DIRECT
1914 def_bool y
1915 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC))
1917 config PCI_MMCONFIG
1918 def_bool y
1919 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
1921 config PCI_OLPC
1922 def_bool y
1923 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
1925 config PCI_DOMAINS
1926 def_bool y
1927 depends on PCI
1929 config PCI_MMCONFIG
1930 bool "Support mmconfig PCI config space access"
1931 depends on X86_64 && PCI && ACPI
1933 config PCI_CNB20LE_QUIRK
1934 bool "Read CNB20LE Host Bridge Windows"
1935 depends on PCI
1936 help
1937 Read the PCI windows out of the CNB20LE host bridge. This allows
1938 PCI hotplug to work on systems with the CNB20LE chipset which do
1939 not have ACPI.
1941 config DMAR
1942 bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
1943 depends on PCI_MSI && ACPI && EXPERIMENTAL
1944 help
1945 DMA remapping (DMAR) devices support enables independent address
1946 translations for Direct Memory Access (DMA) from devices.
1947 These DMA remapping devices are reported via ACPI tables
1948 and include PCI device scope covered by these DMA
1949 remapping devices.
1951 config DMAR_DEFAULT_ON
1952 def_bool y
1953 prompt "Enable DMA Remapping Devices by default"
1954 depends on DMAR
1955 help
1956 Selecting this option will enable a DMAR device at boot time if
1957 one is found. If this option is not selected, DMAR support can
1958 be enabled by passing intel_iommu=on to the kernel. It is
1959 recommended you say N here while the DMAR code remains
1960 experimental.
1962 config DMAR_BROKEN_GFX_WA
1963 bool "Workaround broken graphics drivers (going away soon)"
1964 depends on DMAR && BROKEN
1965 ---help---
1966 Current Graphics drivers tend to use physical address
1967 for DMA and avoid using DMA APIs. Setting this config
1968 option permits the IOMMU driver to set a unity map for
1969 all the OS-visible memory. Hence the driver can continue
1970 to use physical addresses for DMA, at least until this
1971 option is removed in the 2.6.32 kernel.
1973 config DMAR_FLOPPY_WA
1974 def_bool y
1975 depends on DMAR
1976 ---help---
1977 Floppy disk drivers are known to bypass DMA API calls
1978 thereby failing to work when IOMMU is enabled. This
1979 workaround will setup a 1:1 mapping for the first
1980 16MiB to make floppy (an ISA device) work.
1982 config INTR_REMAP
1983 bool "Support for Interrupt Remapping (EXPERIMENTAL)"
1984 depends on X86_64 && X86_IO_APIC && PCI_MSI && ACPI && EXPERIMENTAL
1985 ---help---
1986 Supports Interrupt remapping for IO-APIC and MSI devices.
1987 To use x2apic mode in the CPU's which support x2APIC enhancements or
1988 to support platforms with CPU's having > 8 bit APIC ID, say Y.
1990 source "drivers/pci/pcie/Kconfig"
1992 source "drivers/pci/Kconfig"
1994 # x86_64 have no ISA slots, but do have ISA-style DMA.
1995 config ISA_DMA_API
1996 def_bool y
1998 if X86_32
2000 config ISA
2001 bool "ISA support"
2002 ---help---
2003 Find out whether you have ISA slots on your motherboard. ISA is the
2004 name of a bus system, i.e. the way the CPU talks to the other stuff
2005 inside your box. Other bus systems are PCI, EISA, MicroChannel
2006 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2007 newer boards don't support it. If you have ISA, say Y, otherwise N.
2009 config EISA
2010 bool "EISA support"
2011 depends on ISA
2012 ---help---
2013 The Extended Industry Standard Architecture (EISA) bus was
2014 developed as an open alternative to the IBM MicroChannel bus.
2016 The EISA bus provided some of the features of the IBM MicroChannel
2017 bus while maintaining backward compatibility with cards made for
2018 the older ISA bus. The EISA bus saw limited use between 1988 and
2019 1995 when it was made obsolete by the PCI bus.
2021 Say Y here if you are building a kernel for an EISA-based machine.
2023 Otherwise, say N.
2025 source "drivers/eisa/Kconfig"
2027 config MCA
2028 bool "MCA support"
2029 ---help---
2030 MicroChannel Architecture is found in some IBM PS/2 machines and
2031 laptops. It is a bus system similar to PCI or ISA. See
2032 <file:Documentation/mca.txt> (and especially the web page given
2033 there) before attempting to build an MCA bus kernel.
2035 source "drivers/mca/Kconfig"
2037 config SCx200
2038 tristate "NatSemi SCx200 support"
2039 ---help---
2040 This provides basic support for National Semiconductor's
2041 (now AMD's) Geode processors. The driver probes for the
2042 PCI-IDs of several on-chip devices, so its a good dependency
2043 for other scx200_* drivers.
2045 If compiled as a module, the driver is named scx200.
2047 config SCx200HR_TIMER
2048 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2049 depends on SCx200 && GENERIC_TIME
2050 default y
2051 ---help---
2052 This driver provides a clocksource built upon the on-chip
2053 27MHz high-resolution timer. Its also a workaround for
2054 NSC Geode SC-1100's buggy TSC, which loses time when the
2055 processor goes idle (as is done by the scheduler). The
2056 other workaround is idle=poll boot option.
2058 config OLPC
2059 bool "One Laptop Per Child support"
2060 select GPIOLIB
2061 ---help---
2062 Add support for detecting the unique features of the OLPC
2063 XO hardware.
2065 endif # X86_32
2067 config K8_NB
2068 def_bool y
2069 depends on CPU_SUP_AMD && PCI
2071 source "drivers/pcmcia/Kconfig"
2073 source "drivers/pci/hotplug/Kconfig"
2075 endmenu
2078 menu "Executable file formats / Emulations"
2080 source "fs/Kconfig.binfmt"
2082 config IA32_EMULATION
2083 bool "IA32 Emulation"
2084 depends on X86_64
2085 select COMPAT_BINFMT_ELF
2086 ---help---
2087 Include code to run 32-bit programs under a 64-bit kernel. You should
2088 likely turn this on, unless you're 100% sure that you don't have any
2089 32-bit programs left.
2091 config IA32_AOUT
2092 tristate "IA32 a.out support"
2093 depends on IA32_EMULATION
2094 ---help---
2095 Support old a.out binaries in the 32bit emulation.
2097 config COMPAT
2098 def_bool y
2099 depends on IA32_EMULATION
2101 config COMPAT_FOR_U64_ALIGNMENT
2102 def_bool COMPAT
2103 depends on X86_64
2105 config SYSVIPC_COMPAT
2106 def_bool y
2107 depends on COMPAT && SYSVIPC
2109 endmenu
2112 config HAVE_ATOMIC_IOMAP
2113 def_bool y
2114 depends on X86_32
2116 source "net/Kconfig"
2118 source "drivers/Kconfig"
2120 source "drivers/firmware/Kconfig"
2122 source "fs/Kconfig"
2124 source "arch/x86/Kconfig.debug"
2126 source "security/Kconfig"
2128 source "crypto/Kconfig"
2130 source "arch/x86/kvm/Kconfig"
2132 source "lib/Kconfig"